Methane Hydrates Research at Oak Ridge National

Laboratory

C.J. Rawn, PI T.J. Phelps, Co-PI

M. Elwood-Madden, collaborator

Hydrate Formation and Dissociation in Simulated and Field Samples

1

Current PersonnelTommy PhelpsCo‐PI, microbiology, large vessel experiments, and safety engineering

Claudia RawnCo‐PI, material science, X‐ray/neutron diffraction and crystallography

Ji‐Won MoonPostdoctoral Fellow

Megan Elwood‐MaddenUniversity of Oklahoma

2

Miguel Rodriguez, JrR&D Associate and Technical Resource

Jonathan AlfordPost‐graduate, starting September 08

Hydrate background of PI’sT. J. Phelps, Distinguished staff scientist, 16 yrs at ORNL Published  ~15 papers on gas hydrates, total of ~ 150Trained 25 post‐graduates

Related service includes 1st microbiologist and 1stDOE rep on IODP/ODP USSAC and committees 1999‐2002Since 2006 has served DOT in pipeline related issues

C. J. RawnSenior staff scientist with 11 yrs at ORNLJoint Faculty at the University of Tennessee

Published  ~ 12 papers on gas hydrates, total of ~ 80 Interacts daily with DOE facility users, undergraduates and graduate students

Collaborativepublications with SNS, NIST, USGS, INL, Ga Tech, Texas A&M, Univ. of Oklahoma, Oregon State Univ.

Training since 2006 Hydrate ReviewMegan Elwood Madden ORNL Wigner Fellow – 2005 - 2007Assistant Prof. at the University of Oklahoma

Scott McCallum – post masters student geosciences - 2003 - 2006 Petro-geologist, PA

Phillip Szymcek – post masters student geosciences – 2005 – 2007Petro-geologist, AR

Patricia Taboada-Serrano –2005 – 2008 (Former Fulbright Fellow)

Shannon Ulrich – post bachelors student2006 - 2008 Colorado School of MinesEnvironmental Science and Engineering

4

Facilities and Equipment • In-Situ Diffraction

– Neutron– XRD

• Hydrate synthesis capabilities– Deuterated samples for neutron

diffraction

• Seafloor Processing Simulator– housed in a temperature

controlled explosion-proof cold room

– capable of simulating deep seafloor pressures and temperatures

• Luna Distributed Sensing System (DSS) for observation of hydrate formation/dissociation

5

Time, Temp, Pressure

400

500

600

700

800

900

1000

1100

1200

15 20 25 30 35 40 45 50 55

inte

nsity

2-theta (°)

Methane Hydrate 15K neutron powder diffraction patterns

(selected region, lambda = 1.50 Å)

hydrogenous

deuterated

In-Situ neutron diffraction provides capabilities to do combined time, temperature, and pressure decomposition studies (spallation at the SNS provides the time component).

Two neutron powder diffraction patterns collected on samples provided by the USGS. Red: hydrogenous (H2O), Black: deuterated (D2O) showing how deuteration decreases the background and increases the Bragg scattering detailing atomic positions, lattice parameters, etc.

Spallation Neutrons and Pressure (SNAP)

SNAP Diffractometer allows studies of a variety of samples under extreme pressure and temperature conditions

Applies up to 100 GPa on an ~1mm3 sample

Collaborators: Chris Tulk and Bryan Chakoumakos

This enables us to collect temperature/pressure/time dependent data:

Thermal expansionBulk modulus (compressibility)Dissociation kinetics (formation?)

This new beamline hasIncreased neutron fluxLarge-volume pressure cells Next-generation detectors

In-Situ X-ray Powder Diffraction

• PANalytical (Phillips) X’Pert Pro Diffractometer– Anton Paar TTK 450 low

temperature chamber– X’Celerator detector for fast

data collection

Time/Temperature dependent dissociation studiesOn natural samples

Low Temperature X-ray Diffraction Studies of GOM HydratesCollaborator: R. Sassen (Texas A&M) GOM samples with ~30 – 50% sII hydrate

sII gas hydrate, from a GOM natural gas, dissociated ~188 K (-85 C)Only sII and water ice, no sI noted

193 K 213 K

Collect time dependent data at multiple constant temperatures until 100% decompositionGas Chromatography/Mass Spectometery to analyze gases for gas mass balance

Future studies to determine rate constants and reaction parameters

Temperature dependent data showing dissociation of sII hydrate to water ice

sII hydrate content ~30

Slow decomposition at constant temperature (193 K)

Only sII and water ice, no sI noted

Need for Distributed Sensing System

• 2000 – 2006 hydrate tracked by bulk measurements or visually

• Purchased fiber optic Distributed Sensing System (DSS)

• DSS uses fiber optics to observe temp changes corresponding to hydrate formation (exothermic) or dissociation (endothermic)

CO2-hydrate aggregates

Time-Resolved 3-D temperature monitoring

Visible hydrates

Distributed Sensing System (DSS)The Luna® Distributed Sensing System (DSS)

laser pulses down an optical fiber determine changes due to temperature and strain

Temperature and strain cause the fiber to expand or contract which are noted in the reflection time

Time for the reflection to return is translated into a hybrid temperature strain value (TSV).

Sensors are at 1-cm intervals

Integrated analysis of hydrate formation in heterogeneous systems

In situ optical, pressure, and temperature observations of hydrate in free gas systems

Elwood Madden et al., Marine and Petroleum Geology (in press)

Model of hydrate growth from free gas phase

•Hydrate films observed along the surface of methane gas bubbles

•Films crystallized to form hydrate nodules in sediment

•Massive hydrate deposits form initially in areas of gas bubble accumulation

Suggests in systems containing free gas the stratigraphy, tectonic, and sedimentary structures likely control the location of massive gas hydrate deposits

Elwood Madden et al., Marine and Petroleum Geology (in press)

Corroborates Indian Ocean hydrates observed in sands and fractures (Kastner, Goldschmidt 2008)

Data Collection with the DSS• Fibers were coiled in a spiral

– Attached to a circle of plastic mesh– Beginning of fiber on the outside of the spiral– End of fiber at the center of the spiral

sand25 cm

15 cm

5 cmDSS sensor planes

gas headspace

Synthetic sediment experimentsOttawa Sand/Silt

Saturated to 30% with H2O

Homogeneous experiments

Heterogeneous experimentsWith a 3” layer of silt

Ex-Situ Fiber test• Four fibers and thermocouple

exposed to same conditions

Thermocouple data

0Time (h)

15105 20

Tem

pera

ture

(oC

)

0

5

10

15

20Room temp H2O

Addition of ice H2O

Ice melting and gradual warming

Time (h)

Distance along

fiber (cm)Te

mpe

ratu

re (o

C)

DSS data

Nitrogen Control Experiments

• Four homogeneous sediments experiments

– Two where temperature increases– Two where pressure decreases

(one shown at right)

Tem

pera

ture

(oC

)

Depressurization (160 min)

Fibers show similar overall trendsSome fibers could be more sensitive to changes than others

Distance along

fiber (cm)

Time (h)Note: Fiber 115 always shows reproducible variability despite location in SPS, possibility more sensitive to changes

Methane Experiments• Four homogeneous sediment

experiments• CH4 gas at T/P • < 50 g of hydrate expected to form• ~1 L of CH4 added at 0.6 mL/min

via HPLC pump

Time (h)

Distance along

fiber (cm)Possible hydrate formation indicated by upward arrows and dissociation by downward arrows

Dissociation by

warmingdepressurizing

Tem

pera

ture

(oC

)

Initial vessel cooling

System reaches equilibrium

Depressurization

Warming

FY09 – FY11 Directions for SPS - DSS Experiments

• Homogeneous and Heterogeneous sediment experiments pressuring with CH4

• Large data set analysis• Temp/strain monitored every 60

sec • Plotting the distance as polar

coordinates • Igor Pro, Origin, MatLab

(subcontract with University of Oklahoma)

• Massive amounts of hydrate to compare to earlier CH4 experiments

• Examining relationships between overheating and depressurization for gas production

FY09 – FY11 Diffraction Directions• More in-situ XRD work on natural

(hydrogeneous) samples from Texas A&M

• Time dependent studies (kinetics)• Lattice parameters as a function of

temperature (thermal expansion)

• In house synthesis of deuterated samples for neutron powder diffraction– ORNL’s High Flux Isotope Reactor (HFIR)

powder diffractometer upgrades to be completed in FY09

– SNAP open for general users in FY09– Data collection as a function of pressure

• Dissociation pressures• Bulk modulus from analyzing lattice

parametersas a function of pressure

-5

0

5

10

15

20

0 20 40 60 80 100

ther

mal

neu

tron

coh

eren

t sca

tter

ing

leng

th (f

m)

atomic number

Productivity – Publications 2007 and 2008Elwood Madden, M.E., S.M. Ulrich, T.C. Onstott, and T.J. Phelps, 2007, Salinity-induced hydrate dissociation: a mechanism for recent CH4 release on Mars. Geophysical Research Letters 34, Issue 11, CiteID L11202.

McCallum, S., D. Riestenberg, O. Zatsepina and T. Phelps, 2007, Effect of pressure vessel size on the formation of gas hydrates, Journal of Petroleum Science and Engineering – Natural Gas Hydrate/Clathrate (Elsevier), edited by D. Mahajan, C. Taylor and G. Ali Mansoori, Volume 56, Issues 1-3, p. 54-64, March.

Colwell, F., S. Boyd, M. Delwiche, D. Reed, T. Phelps, and D. Newby, 2008, Estimates of biogenic methane production rates in deep marine sediments at Hydrate Ridge, Cascadia Margin, Applied and Environmental Microbiology, 74: 3444-3452.

Elwood Madden, M.E., P. Szymcek, S.M. Ulrich, S. McCallum, and T.J. Phelps, 2008, (in press) Experimental formation of massive hydrate deposits from accumulation of CH4 gas bubbles within synthetic and natural sediments. Marine and Petroleum Geology

Taboada-Serrano, P. S. Ulrich, P. Syzmcek, S. McCallum, T. J. Phelps, A. Palumbo, and C. Tsouris. 2008. A multi-phase, micro dispersion reactor for the continuous production of methane gas hydrate. (Submitted).

Proceedings:Rawn, C.J., R. Sassen, S.M. Ulrich, T.J. Phelps, B.C. Chakoumakos, and E.A. Payzant, “Low Temperature X-ray Diffraction Studies of Natural Gas Hydrate Samples from the Gulf of Mexico”, Proceedings of the 6th

International Conference on Gas Hydrate (ICGH 2008), CD (2008) (In preparation for a journal)

Ulrich, S.M., M.E. Elwood-Madden, C.J. Rawn, P. Szymcek, and T.J. Phelps, “Application of Fiber Optic Temperature and Strain Sensing Technology to Gas Hydrates”, Proceedings of the 6th International Conference on Gas Hydrate (ICGH 2008), CD (2008) (Topic is in preparation for a journal)

Productivity – Presentations

• 6th ICGH Vancouver July 2008 (Two Presentations)• AGU Fall meetings both in 2006 and 2007• GSA Annual Meeting 2007

• Science and Technology Issues in Methane Hydrate R&D workshop, Hawaii, 2006

• Inter-Laboratory Hydrates Workshop, Sept 2006, CSM

• Hosted Tim Grant at ORNL December 2006

• ORNL Gas Hydrates Workshop February 2007 to inform the ORNL community of special capabilities and ongoing hydrate research conducted at the laboratory, and provided a platform for future collaborations

Other Publications, Milestones, and Quarterly Reports

• Publication planned for the Review of Scientific Instruments on the data collection and processing with the DSS with Luna Technologies

• Publication planned on the time/temperature dependent x-ray diffraction data once more experiments at different temperatures are completed

• All milestones from FY08 FWP completed:– 12/07 Collected data with the DSS with heterogeneous sediment

column– 3/08 submitted report on homogeneous sediment column

experiment (precursor to ICGH paper)– Switched 6/08 (conduct neutron diffraction experiment) with 3/09

(publication on time dependent xrd studies) milestones – ICGH paper on time dependent xrd studies

• Quarterly reports sent to Robert Vagnetti (NETL)

Budget Considerations• In FY08 reduced budget by 15% and delayed capital

equipment request

• FY09 Capital Equipment to design and build a cold-loading system for Paris-Edinburgh pressure cells used on the SNAP beamline– ORNL has several PE cells, and the cooling

capability, but lack a method/system to load cold samples

– This cold loading system would give us the ability to pre-cool and load ices and gas hydrates at liquid nitrogen temperature, into the anvil package

Collaborations: Ga Tech/ORNL

Methane Recovery from Hydrate-Bearing SedimentsWith J. Carlos Santamarina GA Tech Faculty

Coalbed Methane Produced Water Treatmentby Hydrate Formation and Dissociation

With Costas Tsouris, Joint ORNL/GA Tech FacultyDepartment of Civil and Environmental Engineering

Geochemistry of shales associated with methane seep mounds

Analyzing:Oxidation state

C, O, H, and S isotopesCarbonates

Redoxgradients (below)

Geologic indicators of gas hydrate formation and dissociation in the lab and field- examining ~65 million year old carbonate seeps for geochemical and sedimentological traces of gas hydrates

Funded through Oak Ridge Associated Universities

Collaborations: University of OklahomaMegan Elwood-Madden

High Pressure in the Paris-Edinburgh Cell-room T, 2 - 20 GPa (encapsulated gasket ensures isostatic to 10GPa)-with micro-furnace, Pmax 7 GPa at 1200K-with WC anvils 2.0 to 20 GPa

-withsintered diamond anvils to 30 GPa 100 mm3 sample volume

VX14 GPa

VX510 GPa

VX315 GPa

SNAP Paris Edinburgh Pressure Cells

10 GPa Paris-Edinburgh Pressure cell in a dedicated

liquid N2/CCR cooler

26 K